Highest temperature in London on August 11?

Platform comparison

Market context

The market concerns the highest temperature recorded at London City Airport on 11 August 2026, with settlement based on Weather Underground's Daily Observations table rather than summary figures. The 0% crowd probability suggests traders expect the temperature to fall outside whichever range this market has defined as the upper bound, or that uncertainty about the specific threshold is driving minimal trading activity.

London's August temperatures have historically ranged between 20°C and 28°C, with extremes occasionally reaching 30°C during heat waves. The Met Office records show that temperatures above 25°C occur in roughly 60% of August days in the capital, whilst readings exceeding 30°C are rare but not unprecedented—the August 2022 heat wave saw temperatures peak at 40.3°C across parts of England. For a typical mid-August day at London City Airport, which sits in a relatively built-up area with urban heat island effects, traders should reference recent summers' patterns: 2023 saw moderate temperatures around 22–26°C in early August, whilst 2024 experienced more variable conditions.

The critical dependency for this market is the specific temperature range offered as the resolution bracket. Without clarity on whether the upper threshold sits at 25°C, 28°C, or 30°C, traders cannot accurately price the probability of exceeding it. Weather forecasting for August 2026 remains unavailable, making historical climatology the primary analytical tool. Traders should monitor whether the market's definition of the temperature range becomes publicly visible, as this will determine whether the current 0% reflects genuine confidence in cooler conditions or simply reflects the absence of defined resolution criteria.

Methodology

This page tracks Highest temperature in London on August 11? across four political prediction venues. Live odds come from the Polymarket order book (the deepest political prediction-market book). Kalshi is the CFTC-regulated US alternative, Betfair the established UK sports-exchange with politics markets, Manifold the open play-money variant. For users geo-blocked from Polymarket directly, brokers like Trump Prediction provide a 0%-fee route into the same order book.

Resolution & payout

Political markets typically settle on official candidate or agency confirmation. Polymarket uses UMA Optimistic Oracle: a proposer posts the outcome with a bond, the two-hour window opens, then the smart contract pays USDC.

Kalshi settles USD via CFTC clearinghouse, with clearly defined resolution sources (e.g. AP race calls for elections). Betfair settles after the official outcome is registered with the league or agency. Manifold is play-money.

UK Frequently Asked Questions

How accurate are political prediction markets?

Historically more accurate than polls. Polymarket's Brier score on US 2024 elections was ~0.11 — better than 538 (~0.14) and every mainstream poll. Markets aggregate information with real skin in the game.

Can prediction markets influence election outcomes?

Markets reflect expectations rather than create them. Studies show public-facing markets can anchor expectations, but don't influence the underlying outcome. Political markets are information, not advocacy.

How fast do political markets react to news?

High-liquidity markets move within seconds to minutes. A Trump tweet on the economy can shift the "Trump 2024" market 2-5 points before mainstream media has written anything.

Are political prediction markets legal in my country?

It varies. They sit in legal gray areas in most jurisdictions. Polymarket is geo-blocked from US/UK/EU; some broker frontends have a different geo footprint. Trade only with capital you can afford to lose, and only if you understand the legal status in your jurisdiction.

Are UK election prediction markets available from the UK?

Yes. Betfair Exchange and Smarkets offer UKGC-regulated UK election markets (seat counts, party share, constituency results). Polymarket also lists UK election contracts with deeper global liquidity. Betfair winnings are typically tax-free for UK individuals; Polymarket profits are subject to HMRC CGT.